1. Industrial Field of the Invention
The present invention relates to an improvement of a cutting method in the silk screen printing industry. The invention concerns a novel printing method capable of conducting accurate multi-color printing by a single screen, as well as gradational pattern printing, and also, different patterns can be additionally printed over the surface of a printing article which has been already printed, to thereby enable more complicated matters to be printed out.
2. Description of the Prior Art
Silk screen printing methods are classified into a direct method in which a pattern mask is used, an exposure method in which a photosensitive resin film is used, and a cutting method which the present invention intends to improve.
Conventionally, the cutting method has not been commonly employed because the processed film cannot print a stack of many sheets. Further, printing articles are limited to paper and cloth, and regeneration of a screen cannot be carried out.
In order to solve one of the problems of the cutting method that many sheets of paper cannot be printed, there is suggested, manufacturing method of a screen for printing and textile printing which uses a film sheet having such a structure that an adhesive layer is interposed between a film and a base paper. In this conventional example, however, the film is adhered on the screen and continues to be used as it is until the end of printing operation, so that the film is restricted to polyvinyl alcohol or the like which does not dissolve into printing ink. Further, the adhered film becomes loose and separated from the screen after it has been used a plurality of times, and this is a problem in common with a conventional method of varnish paper which is adhered on a screen by heating.
Such a film of polyvinyl alcohol or the like which is cut and adhered on the screen accordingly forms film sections through which printing ink should not be permeated. This relates to a fact that it has conventionally been almost impossible to define or express thin lines and outlines in silk screen printing of the cutting method. That is to say, when the cut film sections are to form non-permeable film sections as they are, it is almost impossible to cut the film along thin and curved lines having a width of several tenths millimeters such as outlines or hair even if it is necessary. Besides, even if cutting can be managed, the cut film sections adhered on the screen have a problem in adhesion strength that the non-permeable film sections cannot maintain its printing faculty through a great many times of printing. This conventional method still involves problems to be solved in respect of the quality of finished printing, the possible number of times of printing, and the like.
Recently, it has been required to print more complicated and finer matters even in silk screen printing of the cutting method.
For instance, it has been expected to enable silk screen printing of the cutting method to express gradational patterns of tone difference and blurring, and to print additional patterns overlapping an already printed color surface, which can otherwise be easily managed in paintings. In silk screen printing of the cutting method, the gradational patterns in the former case have been almost impossible to express, and the dual printing in the latter case has not been easily conducted.